Yes, you can swim off the Toronto Islands, and it is one of the city's most popular summer activities. The islands feature several beautiful beaches, including Hanlan’s Point, Gibraltar Point, Centre Island Beach, and Ward’s Island Beach. Most of these beaches are "Blue Flag" certified, meaning they meet high international standards for water quality, safety, and environmental management. Hanlan’s Point is notable for having a clothing-optional section, while Centre Island Beach is popular for families due to its shallow water and proximity to the Centreville Amusement Park. The water temperature in Lake Ontario can be quite chilly even in peak summer, often hovering around 15°C to 20°C (59°F to 68°F). Lifeguards are typically on duty from June through Labour Day. It is always recommended to check the City of Toronto’s beach water quality reports before heading out, as heavy rainfall can occasionally lead to elevated E. coli levels, resulting in temporary swimming advisories. Despite being in a major metropolitan area, the island beaches offer a surprisingly pristine "cottage country" feel just a short ferry ride from the downtown core.